this fixes #77

src/js/storage.js

@@ -34,7 +34,7 @@
 /******************************************************************************/
 
 µMatrix.saveUserSettings = function() {
-    chrome.storage.local.set(
+    this.XAL.keyvalSetMany(
         this.userSettings,
         this.getBytesInUse.bind(this)
     );
@@ -420,6 +420,8 @@
         delete µm.userSettings.processReferer;
         delete µm.userSettings.spoofUserAgent;
         µm.saveUserSettings();
+        µm.XAL.keyvalRemoveOne('processReferer');
+        µm.XAL.keyvalRemoveOne('spoofUserAgent');
     };
 
     var onSettingsReady = function(settings) {

src/js/xal.js

@@ -80,6 +80,12 @@ exports.keyvalSetMany = function(dict, callback) {
 
 /******************************************************************************/
 
+exports.keyvalRemoveOne = function(key, callback) {
+    chrome.storage.local.remove(key, callback || noopFunc);
+};
+
+/******************************************************************************/
+
 exports.keyvalRemoveAll = function(callback) {
     chrome.storage.local.clear(callback || noopFunc);
 };